The challenges of diagnosis and treatment of rare Prevotella-induced breast abscesses: A retrospective cohort study

OBJECTIVE

Although the genus Prevotella is part of the general human microbiota, species of this anaerobic gram-negative bacterium have been described as causes of persisting nonpuerperal breast abscesses. Collecting punctate samples and testing these samples for anaerobic bacteria is not part of the common diagnostic workflow in atypical breast abscesses. The causative anaerobic micro-organism can remain unclear and patients can be treated with multiple inadequate antibiotics and/or extensive surgical procedures. The aim of this cohort study of Prevotella induced breast abscesses is to gain more insights into the diagnostic procedures and treatment.

METHODS

Medical charts of patients with a Prevotella induced breast abscess between 2015 and 2021, were retrospectively reviewed on patient characteristics, diagnostic procedures, treatment and outcome.

RESULTS

Twenty-one patients were included. Six subspecies of Prevotella were determined by culturing. High susceptibility was observed for amoxicillin/clavulanic acid (100%, n = 12). Nine patients (43%) were treated with antibiotics, eight patients (38%) with antibiotics and incision and drainage, and four patients (19%) with only incision and drainage. Recurrence was observed in nine patients (43%), of whom five patients were treated with antibiotics and three patients had surgery. The mean duration of antibiotic administration in patients with recurrence was significantly shorter compared to those without recurrence (5.6 days vs. 19.5 days, p = 0.039).

CONCLUSION

Specific anaerobic culturing should be common practice in atypical breast abscesses to confirm Prevotella species. The high recurrence rate emphasizes the need of further research for optimal treatment. Prolonged duration of antibiotics could be considered and amoxicillin/clavulanic acid seems to be the first choice.

Abstract P3-12-29: Effect of the COVID outbreak on detection of second primary breast cancer and breast cancer recurrences

Introduction: The COVID-19 pandemic led to a decrease in the incidence of breast cancer diagnoses in the Netherlands. This was due to the encouragement to stay at home, a lack of capacity at the general practitioner (GP) and an increased reluctance of patients to visit the GP. Moreover, from the 16th of March the Dutch breast cancer screening program was halted and gradually restarted from June onwards. Part of the follow-up visits for breast cancer survivors were also postponed or changed to an appointment by phone. However, it is not known how this affected the incidence of second primary breast cancer (SPBC) and pathologically confirmed breast cancer recurrences . Objective: To investigate the effect of the COVID-19 pandemic on the diagnosis of SPBC and breast cancer recurrences. Methods: Women diagnosed with a pathological confirmed SPBC or recurrence (locoregional recurrences (LRR) + distant metastasis (DM)) between January 1st 2017 and February 28th 2021 were selected from the Netherlands Cancer Registry, based on diagnoses of the Nationwide Histopathology and Cytopathology Data Network and Archive (PALGA). Patients with a SPBC or recurrence who had their primary breast tumor diagnosed more than five years ago were excluded. March 1st 2020 till February 28th 2021 was regarded as the COVID-19 period. Incidence was expressed per 100,000 women, who were diagnosed with breast cancer less than 5 years ago, and who were still alive. Incidence of SPBCs and recurrences was calculated for the total COVID-19 period and for four subperiods, and compared with the corresponding periods in 2017/2019 (averaged). Results: A total of 393 patients were diagnosed with a SPBCs in 2017, 340 in 2018, 299 in 2019, 342 in 2020 and 71 up to February 2021. A total of 447 patients were diagnosed with a recurrence in 2017, 520 in 2018, 516 in 2019, 529 in 2020 and 80 up to February 2021. During the COVID-19 period a total of 449 patients were diagnosed with a SPBCs per 100,000 breast cancer survivors, this was comparable to the 445 patients diagnosed per year per 100,000 breast cancer survivors in 2017/2019 (p=0.91) (Table 1). The incidence of SPBCs was significantly lower during March-May 2020 compared to the same period in 2017/2019 (86 vs. 121) (p=0.03), leading to 50 less SPBCs diagnoses. The incidence was higher during June-August 2020 (124 vs. 95), however this was not significant (p=0.09). The incidence of recurrences in the COVID-19 period, and within all four subperiods, was comparable to the incidence in 2017/2019. Conclusion: The COVID-19 pandemic led to a decrease in the detection of SPBCs at the beginning of the pandemic. However, this drop in incidence was caught up in the period thereafter. This might be related to the restart of the regular follow-up visits (partly in real-life consultations), the call to go to the GP in case of complaints and the improved accessibility of the GPs. The incidence of recurrences did not decrease since it includes also DM, which cause worrisome symptoms for which care is sought.

Incidence of pathological confirmed second primary breast cancer and breast cancer recurrencesSPBCP-value1Recurrence2P-value1Reference3445.00.91639.40.63COVID-19 period4448.7658.9March - May reference3120.70.03151.80.64March - May 202085.9142.3June - August reference395.30.09166.40.37June - August 2020124.3185.9September - November reference3125.00.78159.50.54September - November 2020120.5171.8December - February reference3104.80.44166.40.70December 2020 - February 2021117.9159.0Incidence is expressed per 100,000 women who were diagnosed with breast cancer less than 5 years ago and who were still alive SPBC: Second primary breast cancer Bold: incidence in that period of 2020/2021 is statistically significantly lower compared to the incidence in 2017/2019 (averaged) 1. Comparing 2020/2021 with the same period in 2017/2019 2. Recurrence included locoregional recurrences and distant metastasis 3. Reference period: 2017/2019 4. COVID-19 period: March 2020 - February 2021

Citation Format: Anouk H Eijkelboom, Linda de Munck, Jelle Wesseling, Pieter J Westenend, Desirée HJG van den Bongard, Mariëlle PWA Hendriks, Mireille JM Broeders, Luc JA Strobbe, Maud Bessems, Aafke H Honkoop, Marc BI Lobbes, Vivianne CG Tjan-Heijnen, Sabine Siesling, NABON-COVID-19 consortium and the COVID and Cancer Care-NL consortium. Effect of the COVID outbreak on detection of second primary breast cancer and breast cancer recurrences [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-12-29.

Using Guideline-Based Clinical Decision Support in Oncological Multidisciplinary Team Meetings: A Prospective, Multicenter Concordance Study

Background

Multidisciplinary team meetings formulate guideline-based individual treatment plans based on patient and disease characteristics and motivate reasons for deviation. Clinical decision trees could support multidisciplinary teams to adhere more accurately to guidelines. Every clinical decision tree is tailored to a specific decision moment in a care pathway and is composed of patient and disease characteristics leading to a guideline recommendation.

Objective

This study investigated (1) the concordance between multidisciplinary team and clinical decision tree recommendations and (2) the completeness of patient and disease characteristics available during multidisciplinary team meetings to apply clinical decision trees such that it results in a guideline recommendation.

Methods

This prospective, multicenter, observational concordance study evaluated 17 selected clinical decision trees, based on the prevailing Dutch guidelines for breast, colorectal and prostate cancers. In cases with sufficient data, concordance between multidisciplinary team and clinical decision tree recommendations was classified as concordant, conditional concordant (multidisciplinary team specified a prerequisite for the recommendation) and non-concordant.

Results

Fifty-nine multidisciplinary team meetings were attended in 8 different hospitals, and 355 cases were included. For 296 cases (83.4%), all patient data were available for providing an unconditional clinical decision tree recommendation. In 59 cases (16.6%), insufficient data were available resulting in provisional clinical decision tree recommendations. From the 296 successfully generated clinical decision tree recommendations, the multidisciplinary team recommendations were concordant in 249 (84.1%) cases, conditional concordant in 24 (8.1%) cases and non-concordant in 23 (7.8%) cases of which in 7 (2.4%) cases the reason for deviation from the clinical decision tree generated guideline recommendation was not motivated.

Conclusion

The observed concordance of recommendations between multidisciplinary teams and clinical decision trees and data completeness during multidisciplinary team meetings in this study indicate a potential role for implementation of clinical decision trees to support multidisciplinary team decision-making.

Impact on Quality of Documentation and Workload of the Introduction of a National Information Standard for Tumor Board Reporting

PURPOSE

Tumor boards, clinical practice guidelines, and cancer registries are intertwined cancer care quality instruments. Standardized structured reporting has been proposed as a solution to improve clinical documentation, while facilitating data reuse for secondary purposes. This study describes the implementation and evaluation of a national standard for tumor board reporting for breast cancer on the basis of the clinical practice guideline and the potential for reusing clinical data for the Netherlands Cancer Registry (NCR).

METHODS

Previously, a national information standard for breast cancer was derived from the corresponding Dutch clinical practice guideline. Using data items from the information standard, we developed three different tumor board forms: preoperative, postoperative, and postneoadjuvant-postoperative. The forms were implemented in Amphia Hospital’s electronic health record. Quality of clinical documentation and workload before and after implementation were compared.

RESULTS

Both draft and final tumor board reports were collected from 27 and 31 patients in baseline and effect measurements, respectively. Completeness of final reports increased from 39.5% to 45.4% (P = .04). The workload for tumor board preparation and discussion did not change significantly. Standardized tumor board reports included 50% (61/122) of the data items carried in the NCR. An automated process was developed to upload information captured in tumor board reports to the NCR database.

CONCLUSION

This study shows implementation of a national standard for tumor board reports improves quality of clinical documentation, without increasing clinical workload. Simultaneously, our work enables data reuse for secondary purposes like cancer registration.

Impact of the COVID-19 pandemic on diagnosis, stage, and initial treatment of breast cancer in the Netherlands: a population-based study

BACKGROUND

The onset of the COVID-19 pandemic forced the Dutch national screening program to a halt and increased the burden on health care services, necessitating the introduction of specific breast cancer treatment recommendations from week 12 of 2020. We aimed to investigate the impact of COVID-19 on the diagnosis, stage and initial treatment of breast cancer.

METHODS

Women included in the Netherlands Cancer Registry and diagnosed during four periods in weeks 2-17 of 2020 were compared with reference data from 2018/2019 (averaged). Weekly incidence was calculated by age group and tumor stage. The number of women receiving initial treatment within 3 months of diagnosis was calculated by period, initial treatment, age, and stage. Initial treatment, stratified by tumor behavior (ductal carcinoma in situ [DCIS] or invasive), was analyzed by logistic regression and adjusted for age, socioeconomic status, stage, subtype, and region. Factors influencing time to treatment were analyzed by Cox regression.

RESULTS

Incidence declined across all age groups and tumor stages (except stage IV) from 2018/2019 to 2020, particularly for DCIS and stage I disease (p < 0.05). DCIS was less likely to be treated within 3 months (odds ratio [OR]wks2-8: 2.04, ORwks9-11: 2.18). Invasive tumors were less likely to be treated initially by mastectomy with immediate reconstruction (ORwks12-13: 0.52) or by breast conserving surgery (ORwks14-17: 0.75). Chemotherapy was less likely for tumors diagnosed in the beginning of the study period (ORwks9-11: 0.59, ORwks12-13: 0.66), but more likely for those diagnosed at the end (ORwks14-17: 1.31). Primary hormonal treatment was more common (ORwks2-8: 1.23, ORwks9-11: 1.92, ORwks12-13: 3.01). Only women diagnosed in weeks 2-8 of 2020 experienced treatment delays.

CONCLUSION

The incidence of breast cancer fell in early 2020, and treatment approaches adapted rapidly. Clarification is needed on how this has affected stage migration and outcomes.

Achieving best possible cancer treatment outcomes in care pathways through benchmarking: ABC benchmarking

268

Background: Care pathways are used to manage quality in healthcare and concern the organization and standardization of care processes. By benchmarking care pathways, new knowledge is generated that can be utilized to optimize care pathways. A recent development in healthcare is the transformation from volume-based healthcare to value-based healthcare, which amongst others emphasizes the need for IPU (Integrated Practice Unit) development. The ABC-Benchmarking project is an international benchmarking project aiming to further develop the BENCH-CAN pathway benchmark, establish comparative scores on IPU development, and link outcome data to benchmark results. Methods: The 13 step benchmarking process as developed by Van Lent et al. was used. Indicators were primarily derived from the BENCH-CAN pathway benchmark format and secondary from expert opinion. An adapted Delphi method, in which clinical experts on breast and prostate cancer provided feedback in three rounds, was used to select the final set of indicators. The indicator sets containing structure, process and outcome indicators were piloted in 5 centers. Clinical outcome indicators were collected primarily through cancer registries. Site visits were performed to clarify additional questions based on the provided data and to grasp the context of the care pathway. Results: The final set contained 79 indicators for breast and 69 indicators for prostate cancer. Due to differences in registration and data availability of cancer registries not all data could be collected for all centers. Differences between cancer centers were found for example in the measurement of patient reported outcomes and status of the IPU. Aggregated and comparative data can be shown during the symposium. Conclusions: Further validating the pathway benchmark tool and adding more focus to IPU development and outcome indicators led to new knowledge on adding value for cancer patients. Examples given were optimizing care organized in care pathways for breast and prostate cancer patients. The results provided improvement opportunities for all centers. A study into patient involvement in pathway development, evaluation and improvement is also part of this project.

Primary Actinomycosis in the breast caused by Actinomyces neuii. A report of 2 cases

Actinomycosis is a slowly progressive infection caused by anaerobic bacteria, primarily from the genus Actinomyces. Primary actinomycosis of the breast is rare and presents as a mass like density which can mimic malignancy. Mammography, ultrasonography and histopathologic examination is required for diagnosis. Treatment should consist of high doses of antibacterials for a prolonged period of time and possibly surgical drainage. Primary actinomycosis infections are commonly caused by A. israelii. Actinomyces neuii is a less common cause of classical actinomycosis. We present two cases of primary actinomycosis of the breast in two female patients caused by A. neuii.

The isolated perfused rat liver: standardization of a time-honoured model

For many years, the isolated perfused rat liver (IPRL) model has been used to investigate the physiology and pathophysiology of the rat liver. This in vitro model provides the opportunity to assess cellular injury and liver function in an isolated setting. This review offers an update of recent developments regarding the IPRL set-up as well as the viability parameters that are used, with regards to liver preservation and ischaemia and reperfusion mechanisms.

A review of the literature was performed into studies regarding liver preservation or liver ischaemia and reperfusion. An overview of the literature is given with particular emphasis on perfusate type and volume, reperfusion pressure, flow, temperature, duration of perfusion, oxygenation and on applicable viability parameters (liver damage and function).

The choice of IPRL set-up depends on the question examined and on the parameters of interest. A standard technique is cannulation of the portal vein, bile duct and caval vein with pressure-controlled perfusion at 20 cm H2O (15 mmHg) to reach a perfusion flow of approximately 3 mL/min/g liver weight. The preferred perfusion solution is Krebs–Henseleit buffer, without albumin. The usual volume is 150–300 cm3, oxygenated to a pO2 of more than 500 mmHg. The temperature of the perfusate is maintained at 37°C. Standardized markers should be used to allow comparison with other experiments.

[No need to spare the arm after axillary dissection: the prohibition on interventions such as venepuncture is obsolete]

Annually, around 11,500 patients are treated surgically for breast cancer. In the past, 5-25% of these underwent an axillary dissection. This procedure can entail complications such as lymphoedema. Known risk factors are obesity and infections or wounds in the arm concerned. There is a traditional assumption that interventions on this arm, such as venepuncture, infusion or measurement of blood pressure, may induce lymphoedema. This assumption has been queried in recent years. Based on our analysis of the current literature, we believe that the above-mentioned interventions after non-complicated axillary dissection do not increase the risk of lymphoedema or other complications. We recommend changing the policy that prohibits interventions such as venepuncture after axillary dissection.

Preservation of steatotic livers: a comparison between cold storage and machine perfusion preservation

Liver grafts are frequently discarded due to steatosis. Steatotic livers can be classified as suboptimal and deteriorate rapidly during hypothermic static preservation, often resulting in graft nonfunction. Hypothermic machine perfusion (MP) has been introduced for preservation of donor livers instead of cold storage (CS), resulting in superior preservation outcomes. The aim of this study was to compare CS and MP for preservation of the steatotic donor rat liver. Liver steatosis was induced in male Wistar rats by a choline-methionine-deficient diet. After 24 hours hypothermic CS using the University of Wisconsin solution (UW) or MP using UW-Gluconate (UW-G), liver damage (liver enzymes, perfusate flow, and hyaluronic acid clearance) and liver function (bile production, ammonia clearance, urea production, oxygen consumption, adenosine triphosphate [ATP] levels) were assessed in an isolated perfused rat liver model. Furthermore, liver biopsies were visualized by hematoxylin and eosin staining. Animals developed 30 to 60% steatosis. Livers preserved by CS sustained significantly more damage as compared to MP. Bile production, ammonia clearance, urea production, oxygen consumption, and ATP levels were significantly higher after MP as compared to CS. These results were confirmed by histology. In conclusion, MP improves preservation results of the steatotic rat liver, as compared to CS.

[Interval appendectomy as routine therapy or only as indicated: the controversy continues]

Although 3 retrospective studies from the Netherlands conclude that interval appendectomy should only be performed when indicated, i.e. when patients present with recurrent acute appendicitis or persistent pain, there is still no consensus in the literature regarding the management of these patients. This is probably due to the lack of sound studies needed to change the standard treatment and because surgeons prefer to adhere to the traditional strategy of interval appendectomy, although it is based on even less valid arguments. The risk of recurrent appendicitis is low, especially in adult patients. In this setting, the disease is generally less severe, and performing interval appendectomy only as indicated does not increase the risk ofcomplications. In contrast, routine interval appendectomy is associated with increased morbidity, longer hospital stays and greater costs. Colon malignancy, however, should be ruled out in patients over 40 years. It is still unclear whether the conservative strategy should also be preferred for paediatric patients, who may have a higher risk of recurrence. Faster and better diagnosis may further reduce the incidence ofappendiceal mass or abscess.

Wash-out of the non-heart-beating donor liver: a matter of flush solution and temperature?

BACKGROUND AND AIMS

Ischemically damaged donor livers are prone to graft non-function. This can in part be explained by a suboptimal wash-out during procurement. An enriched machine perfusion (MP) preservation solution for livers, named Polysol, was developed. The aim of this study was to investigate the type of flush solution, temperature and anticoagulant content on the wash-out of the non-heart-beating donor (NHBD) rat liver.

METHODS

Rat livers were flushed after 30 min warm ischemia. After excision, livers were reperfused at 37 degrees C, with analysis of damage and function, concerning (1) solutions (University of Wisconsin (UW), histidine-tryptophan-ketoglutarate (HTK) and Polysol); (2) temperature (4 degrees C, 18 degrees C and 37 degrees C); (3) addition of heparin and (4) wash-out followed by 24 h MP.

RESULTS

(1) Reperfusion results were inferior in the UW group; (2) less damage and improved function were seen after wash-out using Polysol at 37 degrees C; (3) No effects were seen of the addition of heparin to Polysol; (4) MP after wash-out using HTK resulted in more liver damage and decreased liver function as compared with wash-out using Polysol.

CONCLUSIONS

Polysol is applicable as a flush solution for the NHBD liver, resulting in equal to better wash-out as compared with UW and HTK. The best temperature for this NHBD wash-out is 37 degrees C.

Machine perfusion preservation of the pig liver using a new preservation solution, polysol

INTRODUCTION

The current gold standard for donor liver preservation is cold storage in a preservation solution (4 degrees C), such as Celsior or the University of Wisconsin solution (UW). Recent studies have suggested the benefits of machine perfusion (MP) over cold storage. To improve the results of MP, an enriched preservation solution (named Polysol) was developed, which in a rat liver preservation model proved to be superior to the UW-gluconate solution. The aim of this study was to assess Polysol in a pig liver preservation model.

MATERIALS AND METHODS

Female pigs (35 to 40 kg) were used as liver donors. After heparinization, the liver was washed out using Ringer's lactate, followed by the preservation solution (4 degrees C). The liver was preserved for 24 hours by either cold storage using Celsior (n=5) or MP using Polysol (n=5). For analysis of liver damage and function, livers were reperfused for 60 minutes using oxygenated Krebs-Henseleit buffer.

RESULTS

CS-Celsior caused significantly more damage compared with MP-Polysol (t=60, AST: 622+/-215 versus 222+/-55; ALT: 17+/-6 versus 5+/-1). Intravascular resistance during reperfusion was significantly higher after CS-Celsior compared with MP-Polysol (t=0, 0.20+/-0.01 and 0.11+/-0.02 mm Hg/mL/min, respectively). No differences were seen regarding ammonia clearance and urea production. In both groups, no bile was produced during reperfusion.

CONCLUSIONS

In an ex vivo pig liver preservation model significantly less damage was observed after machine perfusion preservation using Polysol, in comparison to cold storage using Celsior.

Machine perfusion preservation of the pig liver using a new preservation solution, polysol

INTRODUCTION

The current gold standard for donor liver preservation is cold storage in a preservation solution (4 degrees C), such as Celsior or the University of Wisconsin solution (UW). Recent studies have suggested the benefits of machine perfusion (MP) over cold storage. To improve the results of MP, an enriched preservation solution (named Polysol) was developed, which in a rat liver preservation model proved to be superior to the UW-gluconate solution. The aim of this study was to assess Polysol in a pig liver preservation model.

MATERIALS AND METHODS

Female pigs (35 to 40 kg) were used as liver donors. After heparinization, the liver was washed out using Ringer's lactate, followed by the preservation solution (4 degrees C). The liver was preserved for 24 hours by either cold storage using Celsior (n=5) or MP using Polysol (n=5). For analysis of liver damage and function, livers were reperfused for 60 minutes using oxygenated Krebs-Henseleit buffer.

RESULTS

CS-Celsior caused significantly more damage compared with MP-Polysol (t=60, AST: 622+/-215 versus 222+/-55; ALT: 17+/-6 versus 5+/-1). Intravascular resistance during reperfusion was significantly higher after CS-Celsior compared with MP-Polysol (t=0, 0.20+/-0.01 and 0.11+/-0.02 mm Hg/mL/min, respectively). No differences were seen regarding ammonia clearance and urea production. In both groups, no bile was produced during reperfusion.

CONCLUSIONS

In an ex vivo pig liver preservation model significantly less damage was observed after machine perfusion preservation using Polysol, in comparison to cold storage using Celsior.

Improved machine perfusion preservation of the non-heart-beating donor rat liver using Polysol: a new machine perfusion preservation solution

Waiting lists for transplantation have stimulated interest in the use of non-heart-beating donor (NHBD) organs. Recent studies on organ preservation have shown advantages of machine perfusion (MP) over cold storage (CS). To supply the liver with specific nutrients during MP, the preservation solution Polysol was developed. The aim of our study was to compare CS in University of Wisconsin solution (UW) with MP using UW-gluconate (UW-G) or Polysol in an NHBD model. After 30 minutes of warm ischemia, livers were harvested from rats for preservation by either CS, MP-UW-G, or MP-Polysol. After 24 hours of preservation, livers were reperfused with Krebs-Henseleit buffer (KHB). Perfusate samples were analyzed for liver damage and function. Biopsies were examined by hematoxylin and eosin staining and transmission electron microscopy. Liver damage was highest after CS compared with the MP groups. MP using Polysol compared with UW-G resulted in less aspartate aminotransferase (AST) and alanine aminotransferase (ALT) release. Perfusate flow, bile production, and ammonia clearance were highest after MP-Polysol compared with CS and MP-UW-G. Tissue edema was least after MP-Polysol compared with CS and MP-UW-G. In conclusion, preservation of the NHBD rat liver by hypothermic MP is superior to CS. Furthermore, MP using Polysol results in better-quality liver preservation compared with using UW-G.

Optimization of a new preservation solution for machine perfusion of the liver: which is the preferred colloid?

AIMS

Machine perfusion (MP) has proven to be beneficial in experimental preservation of the liver. The modified University of Wisconsin solution (UW-Gluconate or UW-G) is used as the MP preservation solution of choice. We have developed Polysol, an enriched MP preservation solution based on a colloid. We sought to optimize Polysol by substituting the colloid hydroxyethylstarch (HES) with the colloids dextran and polyethylene glycol (PEG).

METHODS

In an isolated perfused rat liver model, hepatocellular damage and liver function were assessed during reperfusion with Krebs-Henseleit buffer after 24 hours hypothermic MP using Polysol-HES, Polysol-dextran, or Polysol-PEG. Control livers were preserved by MP using UW-G.

RESULTS

Compared to MP-UW-G, MP using Polysol resulted in significantly less damage and improved function during reperfusion. MP using Polysol-dextran or Polysol-PEG resulted in equal or less damage than Polysol-HES. Differences in ammonia clearance and bile production were not significant. Tissue edema was higher after MP using Polysol-HES as compared to Polysol-dextran and Polysol-PEG.

CONCLUSIONS

MP of rat livers for 24 hours using UW-G results in more extensive damage and reduced liver function compared to MP using Polysol. MP using Polysol-dextran or Polysol-PEG results in equal or even better preservation compared to Polysol-HES.

Wash-out of the non-heart-beating donor liver: a comparison between ringer lactate, HTK, and polysol

The solution of choice for wash-out of non-heart-beating donor (NHBD) livers is histidine tryptophan ketoglutarate (HTK). This solution has a lower viscosity, due to absence of a colloid, and is less expensive as compared to the University of Wisconsin (UW) solution. A new preservation solution for machine perfusion was developed, named Polysol. In order to apply Polysol clinically in NHBD organ retrieval, the efficacy as a wash-out solution was investigated.

METHODS

After a warm ischemic time of 30 minutes, the rat liver was washed out via the portal vein with 50 mL of either ringer lactate (RL), HTK or Polysol. After wash-out and harvesting, the liver was reperfused with Krebs-Henseleit buffer. Samples were taken to assess hepatocellular injury and liver function.

RESULTS

Liver damage parameters were elevated in the RL group as compared to the HTK and Polysol groups. Liver/rat weight ratios were significantly lower after wash-out with Polysol. Overall, no differences were seen in ammonia clearance and bile production. In conclusion, wash-out of the NHBD liver with Polysol results in equal to improved reperfusion results as compared to HTK. Polysol is feasible as a wash-out solution in combination with machine perfusion using Polysol.

[Life-threatening infections with a new strain of Clostridium difficile]

Three men, aged 39, 73, and 66 years, respectively, developed an infection with a new strain ofClostridium difficile, ribotype 027.C.difficile-associated diarrhoea (CDAD) occurred in two patients after multiple abdominal surgery and in the third patient one week after autologous haematopoietic cell transplantation. Within a few days, despite antibiotic therapy, all three patients developed severe (pseudomembranous) colitis with sepsis for which admission to the Intensive Care Unit was required. Two patients underwent (sub)total colectomy and received an intensive course of oral and/or rectal vancomycin. In all patients who develop diarrhoea in hospital, especially during or after treatment with antibiotics or chemotherapeutic agents, an infection with C. difficile ribotype 027 should be suspected. Recent outbreaks of this hypervirulent strain of C. difficile have been reported in Canada, the United States, United Kingdom, and The Netherlands. Demonstration of C. difficile toxin in faeces confirms the clinical suspicion of CDAD and ribotyping of the strain may reveal whether the 027 strain is present. For treatment of these 027 infections, vancomycin is preferred to metronidazole. After a severe course of colitis or in case of recurrence a 'tapering and pulse' course ofvancomycin can be prescribed; alternatively, treatment with bovine antibody-enriched whey may be considered. The introduction of this hypervirulent strain has led to reinforcement of the hygienic measures in accordance with the recommendations of the Dutch Working Party on Infection Prevention and a policy to deter the use of fluoroquinolones.

Improved rat liver preservation by hypothermic continuous machine perfusion using polysol, a new, enriched preservation solution

For experimental machine perfusion (MP) of the liver, the modified University of Wisconsin solution (UW-G) is most often used. In our search for an enriched MP preservation solution, Polysol was developed. Polysol is enriched with various amino acids, vitamins, and other nutrients for the liver metabolism. The aim of this study was to compare Polysol with UW-G for MP preservation of the liver. Rat livers were preserved during 24 hours with hypothermic MP using UW-G (n = 5) or Polysol (n = 5). Hepatocellular damage (aspartate aminotransferase [AST], alanine aminotransferase [ALT], lactate dehydrogenase [LDH], alpha-glutathione-S-transferase [alpha-GST]) and bile production were measured during 60 minutes of reperfusion (37 degrees C) with Krebs-Henseleit buffer. Control livers were reperfused after 24 hours of cold storage in UW (n = 5). MP using UW-G or Polysol showed less liver damage when compared with controls. Livers machine perfused with Polysol showed less enzyme release when compared to UW-G. Bile production was higher after MP using either UW-G or Polysol compared with controls. In conclusion, machine perfusion using Polysol results in better quality liver preservation than cold storage with UW and machine perfusion using UW-G.

Machine perfusion preservation of the non–heart-beating donor rat livers using polysol, a new preservation solution

AIMS

The increasing shortage of donor organs has led to a focus on extended criteria donors, including the non-heart-beating donor (NHBD). An optimal preservation method is required to facilitate successful transplantation of these ischemically damaged organs. The recent literature has shown clear advantages of hypothermic machine perfusion (MP) over cold storage (CS). For MP, modified University of Wisconsin perfusion solution (UW-G) is often used, which, however, is known to cause microcirculatory obstruction, is difficult to obtain, and is expensive. Therefore, Polysol was developed as a MP preservation solution that contains specific nutrients for the liver, such as amino acids, energy substrates, and vitamins. The aim of this study was to compare Polysol with UW-G in a NHBD rat liver model.

METHODS

After 24 hours hypothermic MP of NHBD rat livers using UW-G or Polysol, liver damage and function parameters were assessed during 60 minutes of reperfusion with Krebs-Henseleit buffer. Control livers were reperfused after 24 hours CS in UW.

RESULTS

Liver enzyme release was significantly higher among the CS-UW group compared to MP using UW-G or Polysol. Flow during reperfusion was significantly higher when using Polysol compared to UW-G. Bile production and ammonia clearance were highest when using Polysol compared to UW-G. There was less cellular edema after preservation with Polysol compared to UW-G.

CONCLUSIONS

MP of NHBD rat livers for 24 hours using UW-G or Polysol resulted in less hepatocellular damage than CS in UW. MP of NHBD livers for 24 hours using Polysol is superior to MP using UW-G.

The first disposable perfusion preservation system for kidney and liver grafts

Machine perfusion systems for continuous hypothermic perfusion preservation are computer controlled and re-usable. The system of perfusion preservation proved beneficial for for storage of kidneys, particularly those harvested from NHBD donors. The first disposable continuous hypothermic perfusion system which can be used for storage of livers is presented.

Preservation of rat livers by cold storage: a comparison between the University of Wisconsin solution and Hypothermosol

OBJECTIVES

The University of Wisconsin solution (UW) is the gold standard for cold storage (CS) of donor livers. However, UW contains the colloid Hydroxyethyl starch (HES), which may cause perfusion deficits due to its high viscosity. Recently, a new CS preservation solution, Hypothermosol (HTS), was introduced which contains the less viscous colloid Dextran. The aim of this study was to assess HTS as a cold storage solution for preservation of the liver.

METHODS

In an isolated perfused rat liver model, hepatocellular damage was assessed after 24 hours of CS. Liver enzymes were measured during reperfusion with Krebs-Henseleit Buffer. Bile was collected during reperfusion as a parameter of liver function.

RESULTS

CS using HTS showed a significant decrease of ALT and LDH levels (as compared to UW) at all time points during reperfusion. For LDH these results where most pronounced at t=10 min (84 +/- 7.09 vs 113 +/- 7.57: p < 0.05) and t=30 min (149.2 +/- 9.68 vs 194 +/-6.52: p< 0.05). Regarding liver function, more bile was produced after 24 hours CS in HTS, but this did not reach statistical significancy.

CONCLUSIONS

Cold storage preservation of rat livers using Hypothermosol results in equal or even better preservation as compared to cold storage using UW.